Rationale for iNO therapy:

• As a selective pulmonary vasodilator, iNO therapy is an important adjunct to available treatments for newborns with hypoxemic respiratory failure.

Whom to treat:

• Works best in idiopathic PPHN and pneumonia
• Less dramatic response in RDS and Meconium Aspiration syndrome
• Optimal iNO effects seen after optimizing lung volume recruitment and V/Q matching.
• Usually not effective in preventing ECMO in CDH patients, but may be useful as adjunctive therapy or to treat post-ECMO PPHN.
• Low dose iNO (5 ppm) may be useful as adjunctive therapy of severe hypoxemic respiratory failure in premature newborns. Studies show improved oxygenation, fewer ventilator days, and no difference in survival, IVH or PVL.

Role of Echocardiography:

• To rule out structural heart disease, especially those lesions where iNO treatment may be contraindicated (Coartation of the aorta, TAPVR, critical AS, Interrupted Aortic arch, hypoplastic left heart)
• Evaluate for signs of PPHN including an estimation of PA pressures (calculated by measuring the TR jet), and by looking for R->L shunting at the ductus arteriosus or at the foramen ovale.
• Left to Right shunting at the foramen ovale and ductus with marked hypoxemia suggest predominant intrapulmonary shunting, and interventions should be directed toward optimizing lung inflation.
• Signs of left ventricular dysfunction with PPHN predicted a poor response to iNO, and therapy should be directed toward improving cardiac function.

Treatment Strategies: